This was the first study to make preliminary observations on the behaviour of a recently described species, Pomacentrus rodriguesensis from the island of Rodrigues. P. rodriguesensis was observed to be solitary species with a preference for territories in live coral. Individuals fed using a combination of methods, feeding predominantly on plankton, but also occasionally on benthic algae. P. rodriguesensis was found to defend its territory against other individuals. Conspecifics elicited the majority of agonistic responses and P. rodriguesensis also acted aggressively towards benthic feeders such as Pomacentrus pikei and Stegastes limbatus. During summer, P. rodriguesensis also interacted with species of wrasse. It is suggested that the pattern of territoriality observed in P. rodriguesensis serves to reduce the loss of benthic algae to competitors and protect the nest from egg predators.